Interactions between surfactants and polymeric nanostructures have gained increasing attention due to their potential application in many disciplines. In this study, a well-defined random copolymer containing 2-(2-methoxyethoxy) ethyl methacrylate (MEO2MA) and poly(ethylene glycol) methyl ether methacrylate (PEGMA2080) (poly(MEO2MA-co-PEGMA2080)) was synthesized using the atom transfer radical polymerization (ATRP) process, and its thermo-responsive behaviors in aqueous solution were investigated. In comparison to other thermo-sensitive random copolymers based on oligo(ethylene glycol) methacrylates (OEGMA), this copolymer exhibited an unusual thermal induced two-stage aggregation process. The copolymer chains associated at the first thermal transition followed by a rearrangement process at the second thermal transition to produce a stable core-shell micellar structure. Furthermore, the binding interactions between cationic surfactants and this copolymer were examined below and above its cloud point. In general, the binding interactions between cationic surfactants and neutral polymers are weak and cationic surfactants are very selective and only bind to those polymers with specific hydrophobic groups. Significant hydrophobic interactions were observed between surfactant monomers and the polymer backbone. The binding occurred uncooperatively at low surfactant concentration, which was confirmed by electromotive force (EMF) measurements. Moreover, the binding affinity of three cationic surfactants follows the sequence: CTAB > TTAB > DoTAB. Cellulose Nanocrystals (CNC) with diameter of 10-20 nm and length of 200-400 nm, derived from native cellulose, is a promising new class of nanomaterials due to its high specific strength, high surface area, and unique optical properties. Currently, most of researches focused on the improvement of its steric stability, dispersability and compatibility in different solvents or matrices. A thermo-responsive polymer, namely Jeffamine M600 (a 600 Da polypropylene glycol) was grafted on the surface of cellulose nanocrystals (CNC) via a peptide coupling reaction. The better dispersion of the modified CNC in water was demonstrated, and the interactions between surfactants and M600-grafted CNC were investigated via isothermal titration calorimetry (ITC). Three types of surfactants with dodecyl alkyl chain and different head groups, namely cationic dodecyltrimethylammonium bromine (DoTAB), anionic sodium dodecyl sulfate (SDS), and nonionic poly(ethylene glycol) dodecyl ether (Brij 30) were studied. Physical mechanisms describing the interactions of cationic, anionic and nonionic surfactants and M600-grafted CNC were proposed. Chitosan molecules are water-soluble in acidic media due to the protonation of amino groups. However, some applications of chitosan are restricted by its poor solubility in basic media. A biocompatible derivative of chitosan, N-carboxyethylchitosan (CECh) was synthesized by Michael addition reactions, which possessed high solubility in both acidic and basic media due to the modification by carboxyl groups. The aggregation behavior of CECh in aqueous solution under the effects of pH, polymer concentration, as well as a gemini surfactant, was investigated by turbidity, zeta potential, fluorescence spectroscopy, viscosity, and surface tension measurements. This research demonstrates that nanostructures comprising of thermo-responsive copolymers can be controlled and manipulated by temperature and surfactants, and they play an important role in the physical properties of surfactants-polymeric complexes. The results from this research provide the fundamental knowledge on the self-assembly behavior and the binding mechanism of various novel polymeric systems and surfactants, which can be utilized to design and develop systems for personal care formulations and drug delivery systems.

Carbon allotropes such as nanotubes, graphene, and buckyball all preserve the same lattice structure. However, their electronic properties are very different depending on their dimensionality. These nanostructures can be functionalized with other chemical groups or can be used to form complicated molecular structures. By using scanning tunneling microscopy and Raman spectroscopy, the functionalization of carbon nanotubes with fluorine was studied as a potential route to tailoring the electrical and chemical properties of carbon nanotubes, and functionalization and exfoliation techniques of graphite without inducing basal plane defects were investigated. Also, building upon our previous research on nanocars, nanodragsters combining buckyball and p-carborane wheels were studied with scanning tunneling microscopy. Unlike its predecessors, a nanodragster can show interesting motions even at room temperature as well as at elevated temperatures.

Through polarization-dependent magneto-optical absorption spectroscopy, the magnetic susceptibility anisotropy for metallic single-walled carbon nanotubes has been extracted and found to be up to 4x greater than values for semiconducting single-walled carbon nanotubes. Consistent with theoretical predictions, this is the first experimental evidence of the paramagnetic nature arising from the Aharonov-Bohm-phase-induced gap opening in metallic nanotubes. We also compare our values with previous work for semiconducting nanotubes, which confirm a break from the prediction that the magnetic susceptibility anisotropy increases linearly with the diameter.

Hybrid nanostructures are fascinating materials for their promising applications in future nanoelectronics, electrical interconnects and energy storage devices. Practical ways of connecting individual carbon nanotubes to metal contacts for their use as interconnects and in electronic devices have been challenging. In this thesis, carbon nanotube based hybrids that combine the best properties of carbon nanotubes and metal nanowires have been fabricated. The electrical properties and Raman spectra of the hybrid nanowires are also studied. This thesis will focus on our recent results in the development of carbon nanotube hybrids for various applications. Various hybrid structures of multiwalled carbon nanotubes and metal nanowires can be fabricated using a combination of electrodeposition and chemical vapor deposition techniques. Controlled fabrication of multi-segmented structures will be studied. Several novel applications of these structures, for example, as electrodes in ultra-high power supercapacitors, multi-functional smart materials are also studied. The thesis will also highlight the development of carbon nanotube hybrids based smart materials. Hybrid nanowires with hydrophobic carbon nanotube tails and hydrophilic metal nanowire heads, allows for the assembly of spheres in solution. The design and manipulation of these carbon nanotube hybrids based smart structures for various novel applications will be discussed. Such new class of carbon nanotube hybrids surfactants are likely to lead as new tools in various fields such as microfluidics or water purification. In addition, we will also look at other variations of hybrid nanostructures fabricated from our method.

This thesis investigates the structure and location of the nanotechnology enterprise in the United States. Nanotechnology merits focus because of the high degree of innovative activity associated with it and due to its promise for regional economic development. I consider the particular sectoral and technical characteristics of nanotechnology. Building on insights from theories of high-technology industrial evolution, this thesis examines contrasting hypotheses about the location of nanotechnology firms. I find that regional academic R and D, availability of venture capital promote entry of nanotechnology firms.

The study of this project includes nomenclature, methodologies for risk assessment, and the exchange of information on human and ecological toxicology studies in nanotechnology research. The goals are: (1) collecting domestic and international nanotechnology relevant to toxicity information, (2) establishing the flow chart of nanotechnology risk assessment, (3) making suggestions of methodologies for risk assessment on nanotechnology, and (4) establishing the structure of nanoparticles risk management for reference to future nanotechnology risk management. Nanopartilces, quantum dots, fullerenes and carbon nanotubes has been collected in Toxicological information of nanomaterials. This study has established the Precautionary Principle and the preliminary framework for health risk assessment, which could prevent or reduce risks before the completed development of the potential danger, and reply the appeal for developing a standard methodology for risk assessment which is made by European Commission during the Brussels Conference of 2004. Exchange of informations of nanotoxicology allows contact between domestic and international researchers. The methodologies for risk assessment establishes framework for health assessment of risks which could be used to be the direction to develop the internal risks assessment, and is advantageous to the government in management of the risks of nanotechnology.

Nano-sensors, as an application of nanotechnology, are extremely important for environmental, medical and security applications. Terahertz science is an exciting new field that is set to impact the field of sensing to a large extent. I proposed to combine the fields of nanotechnology and terahertz science and develop a molecular nano-sensor that operates at terahertz frequencies. I focused our sensing on energetic materials, particularly nitromethane, and conducted an extensive analysis on its frequency spectrum. The study also focused on designing the nano-sensor and determining its terahertz operation characteristics. I subjected it to various conditions through the use of molecular dynamics simulations. Finally we analyzed the simulation results and provided a proof of the concept that we had a working molecular nano-sensor that operates at terahertz frequencies and senses energetic materials. The results from the frequency analysis of nitromethane showed that the frequency characteristics determined from our simulations were in close agreement with the ones determined experimentally. In addition to this we also successfully demonstrated the use of a Lennard Jones potential to model the CN bond scission of nitromethane. Finally, the results from the interactions between the nano-sensor and nitromethane showed that the presence of nitromethane causes sufficient change in the terahertz frequency characteristics of the nano-sensor providing a means to detect nitromethane.

Thesis (M.S.) --Marshall University, 2008. / Title from document title page. Includes abstract. Document formatted into pages: contains 51 pages. Includes bibliographical references (p. 37-38).

Thesis (M.S.) --Marshall University, 2008. / Title from document title page. Includes abstract. Document formatted into pages: contains 51 pages. Includes bibliographical references (p. 37-38).

Thesis (M.S.)--West Virginia University, 2003. / Title from document title page. Document formatted into pages; contains xi, 149 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 135-149).